What can flux pinning be used for?

Flux pinning is desirable in high-temperature ceramic superconductors to prevent “flux creep”, which can create a pseudo-resistance and depress both critical current density and critical field.

What is vortex pinning?

Pinning force is a force acting on a pinned object from a pinning center. In solid state physics, this most often refers to the vortex pinning, the pinning of the magnetic vortices (magnetic flux quanta, Abrikosov vortices) by different kinds of the defects in a type II superconductor.

What is Meissner effect?

Meissner effect, the expulsion of a magnetic field from the interior of a material that is in the process of becoming a superconductor, that is, losing its resistance to the flow of electrical currents when cooled below a certain temperature, called the transition temperature, usually close to absolute zero.

What is the purpose of flux pinning in ceramic superconductors?

Flux pinning is desirable in high-temperature ceramic superconductors to prevent “flux creep”, which can create a pseudo-resistance and depress both critical current density and critical field. Degradation of a high-temperature superconductor’s properties due to flux creep is a limiting factor in the use of these superconductors.

What is the difference between Meissner effect and flux pinning?

Flux pinning. This phenomenon is closely related to the Meissner effect, though with one crucial difference — the Meissner effect shields the superconductor from all magnetic fields causing repulsion, unlike the pinned state of the superconductor disk which pins flux, and the superconductor in place.

How do you calculate flux pinning force?

Flux pinning is determined by spatial perturbations of the free energy of the vortex lines due to local interactions of their normal cores and screening currents with these microstructural imperfections. In addition, the vortex structure is subjected to the Lorentz force FL = J × B of the macroscopic current density J.

What happens when a superconductor is thinned?

The thinner the superconducting layer, the stronger the pinning that occurs when exposed to magnetic fields. Since the superconductor is pinned above the magnet away from any surfaces, there is the potential for a frictionless joint.